100 QUARTERLY CHRONICLE. 



secondary value. Do we not know, for instance, that both 

 in Annelids and in Nematoids, which, as a rule, have the 

 sexes separate, a certain number of hermaphrodite species 

 are found? We knov,^ also some Trematods which are dioe- 

 cious in a group, otherwise entirely hermapln^odite. And 

 recently in the group of the hermaphrodite Planarians, has 

 not a dioecious species been made known [Planaria dioica of 

 St. Vaast, described by M. Claparede) ? Thus the discovery 

 made by M. Keferstein at Saint-Malo of an hermaphrodite 

 Nemertine, is not at all surprising. But it is nevertheless 

 very important, as it is the first case of hermaphrodism in 

 this group. In this animal, to which M. Keferstein gives the 

 name of Borlosia hermaphroditica, the testicles have been found 

 filled with ripe zoosperms and tlie ovaries full of ovules in 

 course of formation. The author having only studied a single 

 individual, one may suppose that the organs designated by 

 him testicles are only spermatic receptacles filled with sperm. 

 However, Professor Keferstein believes that he has reason to 

 be convinced that such an interpretation is false. However 

 that may be, the author suggests that the discovery of an 

 hermaphrodite Nemertine throws some light on the Nemertians 

 in the perivisceral cavity of which Max Schultze, Claparede, 

 and Keferstein himself have found small, living Nemertians 

 well developed. 



Robins' Journal de TAnatomie. January, 1868. "Researches 

 on the Nerves of the Neurilemma, or Nervi-nervorum," by M. 

 C. Sappey. — The neurilemma receives nerve-fibres which are 

 to the nerves what the vasa vasorum are to the vessels, whence 

 the name of nervi-nervorum, under which M. Sappey proposes 

 to describe them. Their existence in the fibrous coat of the 

 nerves had not yet been pointed out ; it is constant neverthe- 

 less, and can be easily demonstrated. The disposition which 

 the nervi-nervorum take in the neurilemma differs little, 

 however, from that which the nervous ramifications in the 

 other dependencies of the fibrous system present. Like these, 

 they follow in general the arteries : like these also, they 

 anastomose freely. It is not only in the common or princi- 

 pal sheath that one meets them, but also on those which 

 surround the principal fasciculi, and the tertiary fasciculi. 

 M. Sappey has also followed them on to the sheaths of the 

 secondary fasciculi. But, in proportion as the calibre of the 

 sheath diminishes, they become more delicate and fewer. 

 One never sees them extending on to the envelope of the 

 primitive fasciculi, (an envelope which is quite different from 

 the preceding and which has been studied by M. Ch. Pi^obin, 

 under the name of perineure (' Comptes Keudus,' 1854). 



